Study lays out plan for super-fast charging network

Source: Peter Behr, E&E News reporter • Posted: Friday, March 8, 2019

To put the next generation of electric vehicles on equal footing with gasoline-power competition, their sticker prices must align, a convergence that EV optimists believe will happen before the end of the next decade.

And the recharge of an EV’s battery may have to match the five minutes that motorists today typically spend filling up at highway service stops, a new analysis of the electric vehicle outlook concludes.

A solution: Put direct current super-fast charging stations at highway service centers located close to existing power transmission substations, minimizing the investment in new power delivery infrastructure, a study by Brattle Group researchers recommends.

Fast-charging stations — thought to be a vital factor in customer acceptance of EVs — require large amounts of power. Building these stations next to electric grid substations would accelerate the spread of public charging and make the best use of the current power line system, said the Brattle Group authors, Jürgen Weiss, Michael Hagerty and Maria Castañer.

The Brattle report, to be released today, was commissioned by WIRES, an advocacy group calling for expansion of U.S. transmission networks to increase access to renewable energy supplies.

It adds new detail to the riddle of how fast American motorists will warm to electric vehicles. It’s a question that is studded with still-undefined factors such as the success of research on battery improvements, the ability of new EVs to handle fast charging, and the pace of a build-out of fast-charging station infrastructure, experts say.

Creating a significantly improved lithium-ion battery for fast charging requires new science, David Howell, deputy director of the Department of Energy’s Vehicle Technologies Office told E&E News last year. “You have to get some research breakthroughs,” he said. “Over the next four to seven years, you’re going to have an affordable EV battery that can be fast-charged for a good portion of its [overall] charges” (Energywire, Nov. 8, 2018).

Most public charging facilities today offer “Level 2” service from a 240-volt connection. A full recharge may take eight hours or more, depending on the vehicle model. Fast charging dramatically lowers the wait.

Citing a DOE study, the Brattle researchers sketched a future in which 400 and 800 fast-charging stations would be built along highways spaced 35 to 70 miles apart.

They worked out that there are about 400 substation transformers of an appropriate size on existing power line routes that are less than a mile from major highway exits where service stations are commonly found. An additional 1,500 substation transformers are within 2 miles of exits. The approach isn’t the full answer, the Brattle report said. But it has early adopters already.

Electrify America, a battery subsidiary of Volkswagen AG, plans to spend $235 million over the next three years to build charging stations in cities and highways, making it far and away the front-runner in U.S. public charging station deployment (Energywire, Feb. 8).

Most of its charging station deployment will be in cities, but the company also wants to build 300 fast-charging stations in 39 states spaced about 70 miles apart (Energywire, Jan. 3).

National Grid, Britain’s transmission system operator, is currently connecting super-fast charging stations at 50 highway sites directly to its transmission network, the Brattle report said.

The public value of vehicle electrification depends on removing the climate-altering carbon emissions from conventional vehicles’ gasoline engine operations and replacing that with battery power replenished largely with zero-carbon electricity, climate action advocates note.

WIRES said it believes that will be the outcome, and the increase in wind and solar power will require a big expansion of U.S. high-voltage networks.

The study estimates that $30 billion to $90 billion in new high-voltage power lines will be needed in the United States. by 2030 to supply new sources of low-carbon energy for a vastly expanded demand for electricity with electric vehicles taking 20 percent to 40 percent of new vehicle sales, and electrification of home heating also expanding. The number would climb to $200 billion to $600 billion between 2030 and 2050.

Hitting the 2030 target would require the equivalent of $3 billion to $7 billion a year, representing a 20 percent to 50 percent increase over average transmission spending now.

To deliver much greater supplies of electric power over the 2030-2050 period could take as much as $25 billion per year in new power line investments, an increase of 170 percent over the annual average for the past decade.

“The resulting impact on customer rates is likely very modest or even beneficial,” the Brattle authors concluded.

Transmission costs are a small part of customer electricity bills. And costs of the additional transmission will be spread across a larger demand for power.

Beyond the cost-and-benefit equation, the Brattle report predicts electric vehicle adoption will track state-by-state political support for clean energy policies.

Just over half of the states have long-term greenhouse gas reduction policies, but the percentage of populations covered by such policies ranges from 99 percent in the Pacific Northeast to zero in the south-central region of the United States, the report said.